In a groundbreaking study, researchers have discovered that cuttlefish possess the remarkable ability to delay gratification—a trait traditionally associated with humans and certain intelligent animals.
This finding not only challenges our understanding of invertebrate intelligence but also provides insight into the evolutionary development of cognitive functions.
The Cuttlefish Marshmallow Test
The study, published in Proceedings of the Royal Society B, adapted the famous “marshmallow test”—a psychological experiment designed to assess self-control in children—for cuttlefish.
In the original test, children were given a choice: consume one marshmallow immediately or wait for a period to receive two marshmallows.
Similarly, researchers presented common cuttlefish (Sepia officinalis) with a choice between an immediate, less preferred food (prawns) and a delayed, more desirable meal (live shrimp).
Astonishingly, all six cuttlefish in the experiment demonstrated self-control, tolerating delays of up to 130 seconds to obtain the preferred prey.
This level of delayed gratification is comparable to that observed in large-brained vertebrates such as chimpanzees, crows, and parrots. – ScienceDaily
Link Between Self-Control and Learning Performance
Further analysis revealed a correlation between self-control and learning performance in cuttlefish. Individuals that exhibited longer delay periods were also quicker to adapt in subsequent learning tasks.
In these tasks, cuttlefish were trained to associate a visual cue with a food reward, and then the situation was reversed, requiring them to learn a new association.
Those that adapted more rapidly to the changing conditions also demonstrated greater self-control.
This suggests a link between self-control and cognitive flexibility, indicating that cuttlefish with better learning performance might improve effective decision-making when delaying gratification. – Journals | Royal Society
These findings challenge the common assumption that complex cognitive abilities, such as self-control and learning flexibility, are exclusive to vertebrates with large brains.
Cuttlefish, cephalopods known for their unique behaviors and advanced nervous systems, exhibit these traits despite lacking the social structures or tool-use behaviors typically associated with delayed gratification in other species.
This discovery suggests that such cognitive abilities may have evolved independently in cuttlefish, possibly as a byproduct of their need to optimize foraging strategies in predator-rich environments. – ScienceDaily
Evolutionary Implications
The evolution of self-control in cuttlefish may be linked to their survival strategies. Cuttlefish spend most of their time camouflaging, sitting and waiting, punctuated by brief periods of foraging.
They break camouflage when they forage, exposing themselves to predators. Therefore, the ability to delay gratification could help them optimize foraging by waiting to choose better quality food, minimizing exposure to predators.
Conclusion
This study provides compelling evidence that cuttlefish possess cognitive abilities previously thought to be exclusive to certain vertebrates.
The ability to delay gratification and the observed link between self-control and learning performance in cuttlefish offer new insights into the evolution of intelligence.
These findings underscore the importance of considering a broader range of species when studying cognitive functions and challenge existing perceptions of invertebrate intelligence.
References
- Alexandra K. Schnell, Markus Boeckle, Micaela Rivera, Nicola S. Clayton, Roger T. Hanlon. “Cuttlefish exert self-control in a delay of gratification task.” Proceedings of the Royal Society B: Biological Sciences, 2021; 288 (1946): 20203161.
- Marine Biological Laboratory. “Fast-learning cuttlefish pass the ‘marshmallow test’.” ScienceDaily, 2 March 2021.
- Diana Kenney. “Cuttlefish can pass the ‘snacking test,’ study finds.” University of Chicago News, 3 March 2021.
